The disclosure relates to a hydraulic arrangement for supplying a consumer or actuator.
According to the prior art, pumps with an adjustable delivery volume, inter alia, are used to supply a consumer (for example, cylinder or motor), the speed of which (for example, movement or rotational speed) is to be capable of being controlled or regulated. Here, a first basic principle is known, in which the rotational speed of a fixed displacement pump can be changed via an electric motor which can be regulated. According to a second basic principle, the delivery volume of a constantly driven variable displacement pump is changed via its adjusting device. Here, its geometric displacement volume is changed. For example, the stroke of its pistons is changed, which stroke said pistons perform during one revolution of its rotor. The consumer can be moved at different speeds (in the case of both basic principles) via the different delivery volumes.
Document DE 10 2011 120 767 A1 has disclosed a hydraulic arrangement for supplying a differential cylinder which can be operated bi-directionally and correspondingly has two working connectors which can both be connected to a pump and to a tank. The pump has an adjustable delivery volume. Furthermore, the arrangement has a switching valve for each of the four main lines. The four main lines result from the fact that the pump can be connected to the two working connectors and the two working connectors can be connected to the tank. The actuation of the four switching valves takes place by way of pulse width modulation, that is to say by way of opening pulses which are of different lengths, or by way of opening pulses which are even shorter, in which the respective valve body does not reach its open end position before it falls back again into its closed position (ballistic behavior).
During operation of the arrangement, a decision is made by a logic circuit depending on the state and the position of the piston of the differential cylinder as to whether the pump or a switching valve of the switching valve arrangement is actuated, in order to move the piston as requested.
A disadvantage of arrangements of this type is the limited throughflow quantity which results from the series connection of the pump and the switching valves.
In contrast, the disclosure is based on the object of providing a hydraulic arrangement for supplying a consumer or actuator, in which hydraulic arrangement the energy efficiency is improved further, and in which, in particular, the maximum throughflow quantity and therefore the maximum speed of the consumer are increased.